Object showing up strange in render
You have enabled Shadow Catcher the object.

Select it, go to the object properties in the Properties area, uncheck Shadow Catcher.



Shadow Catcher objects will appear as a transparent mask except for the shadows.


  [The shadow catcher enables] the object to only receive shadow rays. It is to be noted that shadow catcher objects will interact with other CG objects via indirect light interaction. This feature makes it really easy to combine CGI elements into a real-world footage.  


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